McGwire had turned into a baseball recluse, a pariah, unable to show his face at a ballpark (outside of St. Louis, anyway; there, he still was revered) for fear of having to answer all those nagging questions. Now, at least, McGwire can come out into the sunshine again.

Yet as heartfelt as McGwire tried to be, as anguished as he genuinely appeared to be in his interview with Bob Costas on MLB Network, it was too late. And, especially, too little.

Like Alex Rodriguez, like Andy Pettitte, like Jason Giambi, McGwire confessed because he had to confess. It was a convenient truth, a necessity to clear his path for returning to baseball in 2010 as Cardinals hitting coach.

I suppose McGwire could have continued to refuse to “talk about the past,” as he did so infamously to Congress in 2005. But the weight of the skepticism and finger-pointing would have distracted from his ability to do his new job.

Now, at least, it’s out there, even if one strongly suspects that had Tony La Russa not coaxed him out of retirement, McGwire would’ve remained in virtual hiding. Never mind that an earlier confession, unsolicited and not tied to any new revelation or job, could have hastened baseball’s healing process from the steroids blight that continues to fester.

But better late than never. McGwire still had a golden opportunity for the most meaningful, complete and substantive mea culpa offered by any steroids-using player. And this is where he truly fell short on Monday.

To his credit, McGwire didn’t mince words or employ euphemisms that danced around the truth. He flat-out confessed: “I used steroids during my playing career and I apologize.”

And he didn’t try to claim it was a one-time thing; he admitted to juicing up as far back as 1989, and doing so during his record-breaking 1998 season, in which he hit 70 homers to break Roger Maris’ record.

It was impossible to watch McGwire with Costas and not realize the tremendous emotional toll this confession is taking on McGwire. The torment is sincere. As a fellow human, it’s just as impossible not to feel compassion. And I believe that forgiveness will surely follow, and I’m on board. McGwire is hardly the only player from his era to fall victim to the lure of steroids.

Yet the part that bothers me, and many others, is McGwire’s refusal to link his steroids use to his accomplishments. He did numerous interviews on Monday, including the extensive one with Costas, and clung to the insistence that he used steroids only to heal from injuries and prevent future injuries.

“I did this for health purposes,” he said. “There’s no way I did this for any type of strength use.”

That simply stretches his credibility, as when he told Costas that the steroids didn’t give him any more power.

“I was given a gift to hit home runs,” he said, adding that he could have done so without performance-enhancing drugs.

True, he did hit 49 as a 23-year-old rookie in 1987, presumably still clean (and this I do believe). But McGwire’s career had fizzled until he revitalized himself with the help of PEDs in the 1990s, culminating with a stretch of 52, 58, 70 and 65 homers in a four-year span from 1996 to 1999.

Anyone who remembers the behemoth that sent jaw-dropping blasts into parts of stadiums not reached before or since (except perhaps by Barry Bonds) will have a hard time buying that steroids didn’t enhance that power.

McGwire’s confession isn’t likely to get him into the Hall of Fame. If anything, it will take away votes from those who have been saying they didn’t have proof he juiced. Now there’s indisputable proof, beyond what our own eyes already told us. For those of us grappling with Hall of Fame voting in the steroids era, the task became even more convoluted, if that’s possible.

McGwire had a chance Monday to set a standard of honesty and contrition for future steroids confessors to follow (and this won’t be the last soul cleansing, I promise).

But Big Mac, the man who unleashed the mightiest cuts I’ve ever seen, checked his swing.